At first glance, Berlin's Sauvage restaurant looks much like many of the German capital's other trendy eateries.
But take a closer look at the chalkboard out front and you'll discover they are embarking on a culinary shake-up that takes its inspiration from the Stone Age.
Proudly announcing a 'Real Food Revolution - Paleolithic cuisine!', there is no cheese, bread or sugar available, only fare accessible to our hunter-gatherer ancestors more than two million years ago.
Back to basics: Sauvage kitchen assistant Kawan Lofti holds a dish made entirely of ingredients which our Stone Age ancestors would have used
The restaurant menu shows a stereotypical image of modern humanity's forbearer, the jutting profile of a hirsute caveman.
Inside, diners eat at candle-lit tables with a contemporary cave painting hanging in the background, according to Spiegel Online.
Sauvage, which is also the French word for 'savage' or 'wild,' is part of the Paleolithic diet movement and claims to be first of its kind in Europe.
That means serving only organic, unprocessed fruit and vegetables, meat, fish, eggs, nuts, seeds, and herbs.
The truly obsessed build an entire lifestyle around the concept, mimicking caveman-era exercise.
This can involve lifting boulders and running barefoot, with some even emulating the blood loss they believe Stone Age hunters might have experienced in pursuit of their dinner by donating blood every few months.
But guests at Sauvage can try 'Paleo' without feeling obligated to take on a strictly Stone Age lifestyle.
Sauvage's Boris Leite-Poço told Spiegel Online of the growing interest in caveman cooking.
He said: 'Many people think the Paleolithic diet is just some hipster trend, but it's a worldwide phenomenon, with an online community that spans the globe.